This invention relates generally to the field of thin film microcircuit technology, and more particularly to the formation of connections between metalizations at the same or different elevations and requiring a step-over of one or more insulator edges, for example of a dielectric layer separating a capacitor plate metalization from a substrate supported metalization in a monolithic capacitor device.
Because the evaporation and sputtering metalization techniques such as are usually used in making step-over connections deposit metal somewhat directionally, like a snowfall, the build-up is greatest on more or less horizontal surfaces, and least on vetical or steeply sloping surfaces. Accordingly, the quality of a conventional step-over connection is dependent upon the size and character of the insulator edge. Many insulators, such as silicon nitride used on GaAs monolithic devices, are not amenable to producing smoothly sloped edges. Hence the step-over problem is difficult if not impossible for these insulators. Even where epitiaxial growth of silicon nitride produces smaller steps and more rounded edges, production yield rates are lower than are desirable.